6 Controversial Things I Believe About The Boeing 737 MAX

Many readers believe that the Boeing 737 MAX should never fly again. I disagree. I believe that while there were design flaws, those have been addressed, and regulators are inherently conservative and so it’s likely taking longer than it should to allow the plane to operate commercial flights. I will fly the aircraft again, and you will probably will too.

  1. Aviation accidents almost never have a single cause. Lion Air installed a faulty angle of attack sensor into its 737 MAX that crashed. Crew the day before the crash experienced similar issues with the aircraft, but handled the issue differently. The experience wasn’t written up properly. Different pilots, without the information from the day before, weren’t able to overcome a flight situation created by a combination of a faulty part and a MAX design flaw. Ethiopian crew disengaged MCAS but left the plane at full takeoff power which magnified challenges recovering control of the aircraft.

  2. Relying on a single angle of attack sensor to trigger the MCAS flight law shouldn’t have been acceptable. There were mistakes made in designing the aircraft that shouldn’t have gotten signoff at Boeing, and shouldn’t have been ok with the FAA either (self-certification though is not to blame). Yet the MAX was safe compared to other modes of transport even with its design flaws. Those have received tremendous scrutiny and appear to have been resolved.

  3. Regulators are inherently conservative. No one wants to be blamed if the plane is re-certified and something bad happens, no matter how unlikely that is. Evenually there will be another incident somewhere in the world with an Airbus jet, and there will be an incident with a Boeing jet also. No one wants to have signed off on the return of the MAX if that Boeing incident is with one of those aircraft even if it’s unrelated to issues raised after the Lion Air and Ethiopian crashes.

  4. The Boeing 737 MAX will fly again. Airbus can’t ramp up narrowbody production quickly enough. The known harm to Boeing’s business has already been largely capitalized into its stock. Absent any new negative information they face greater risk from the global economy reducing demand for aircraft than from the 737 MAX.

  5. When the MAX comes back into service some people will briefly avoid it. There will be a rash of stories ‘is it safe?’ and ‘here’s how to know if you’re scheduled to fly on a MAX’. Those will die down, and as long as the plane continues to fly safely concern over the aircraft will subside. Remember all the people who swore they’d never fly United again after David Dao was dragged off a regional jet?

  6. Even if you say you won’t fly the MAX again, I bet that you will. The bar for this plane to fly is higher than any other aircraft in the world, and once it’s flying it will have exceeded that bar. About 5000 of them have been ordered. American, United, Southwest and Air Canada all have MAX aircraft in their fleet. Once the plane flies again, and does so safely, it will become ubiquitous in aviation – and we’ll all wind up flying the aircraft.

The MAX is ready to fly at this point. When do you think regulators in the U.S. will sign off? And how long will it take other countries to follow suit once they do?

About Gary Leff

Gary Leff is one of the foremost experts in the field of miles, points, and frequent business travel - a topic he has covered since 2002. Co-founder of frequent flyer community InsideFlyer.com, emcee of the Freddie Awards, and named one of the "World's Top Travel Experts" by Conde' Nast Traveler (2010-Present) Gary has been a guest on most major news media, profiled in several top print publications, and published broadly on the topic of consumer loyalty. More About Gary »

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  1. #3 is not at all clear to me. Regulators easily become co-opted by those they regulate, and the revolving door between FAA and Boeing made this all the more acute. While Boeing has gotten some very well deserved scrutiny for its egregious behavior, very little has changed with the culture of the FAA. I certainly don’t trust the people in the FAA to keep me safe.

  2. Given what we are beingbtold about the fixes Boeing is making I see two potentially fatal flaws.
    1) the MCAS software is teportedvas being patched.
    Every patch fixes one problem and introduces 6 new bugs (Progammers unwritten rule).
    Never patch critical sofware, rewrite it from the ground up.
    2). Having the two flight computers on board watch eachother to see if ther are interpreting daya correctly is like asking two 5 year old boys to share a favorite toy, and play nice.
    It is hoong to go south at some point, and then both computers are locked up.

    But Boeing is taking the quick route and spinning it for all it is worth because this could hurt thete profits badly.

  3. There was a tv show (airline disasters?) that would go back and review plane crashes. Except in rare cases, it usually involved a series of mishaps.

    And I could never imagine having two sensors on an aircraft but deciding to use only 1 of them. That just is laziness. Not to mention making it so hard to give control back to the pilot. That is another serious mistake.

    I’ve worked as an engineer in a variety of fields (hardware, software, computer security) and sadly there are a number of bad and lazy engineers. They don’t think things out, especially on edge cases. And worse there are too many terrible managers whose only interest is in meeting deadlines at all costs. So sadly this stuff doesn’t surprise me.

    I’m working on some special software now that was previously fielded and we’ve found several bugs that should have been caught, fortunately the software is used for communications and not for a critical use. I’m just thankful there are enough backups and accidents don’t happen more often.

  4. Would I be correct in saying that the Max REQUIRES software to fly safely whereas every other Boeing/Airbus plane in recent memory DOES NOT require software to fly safely?

    I’ve written this here before, and no-one has ever countered this point. If true, signing off the Max means that we are comfortable with a plane that cannot fly wholly under the usual laws of flight. It is for this sole reason that I believe it will never fly again – let’s not get blindsided by the massive size of the order book and the lack of an alternative to quickly replace most of those orders.

    Would love if someone more knowledgeable could comment on this direct point.

  5. Random thoughts….

    In the case of the FAA and its regulators, they passed off too much of the inspection duties to Boeing itself — the proverbial fox guarding the henhouse. Clearly NO ONE at Boeing wanted this to happen; on the contrary, Boeing, its current employees and its shareholders had a lot riding on the MAX having a successful launch. Now they have a strong incentive to make it right…stronger than before, because now it threatens the entire commercial airplane manufacturing side of Boeing, not simply the latest model of a successful line.

    I agree that, once the MAX is declared safe to resume commercial aviation, it *should* be the “safest” plane in the sky. But this is contingent on the FAA, not Boeing, doing the inspections (the FAA said they are going to inspect each plane individually) — and they are under such scrutiny for “screwing up” in the first place…I can’t imagine the FAA would re-certify the MAX unless they were absolutely, positively sure.

    Will *I* personally fly the MAX? I haven’t yet, and while I prefer Airbus A320/321s, I have no doubt that — once it’s airborne again — it will be unavoidable…

  6. This is the reality: Boeing has gone from being an iconic brand, universally trusted and respected, to one synonymous with corner-cutting, greed and duplicity. It will take decades to regain what has been lost, if ever. Meanwhile those responsible remain at the helm…truly bizarre in the context of accepted norms of accountability.

  7. Nothing is unavoidable, all depends how hard you try
    I have not flown United since the Dr Dao incident

  8. The fundamental problem with the Max is that it was not properly tested and certified, it is not clear where the deficiencies in the test program lie. Ultimately the known faults need rectifying and the entire test program needs to be undertaken to finally lay to rest any doubts that remain regarding the design and airworthiness of the Max.

  9. I think that you may be underestimating the average Joe, and how worried they are about flying the Max. As the known travel guru at work, I have had people ask me how to avoid the max as they are wanting to book a spring break trip to Hawaii on Westjet. Another person is worried about their trip to Phoenix.

    But I do agree, a couple of years after the MAX is recertified and without incident it will pass.

    My question I wish could be answered is can the MAX be flown without software and by pilot alone? In other words does the MAX need the software or if the software crashes can a Pilot actually safely fly the jet?

  10. @greg a pilot can fly safely without this software. The
    Plane had to act the same way as the earleir 737s to be certified as part of that program.

    The moved engines give the aircraft a tendency to pitch down under certain conditions. A pilot can compensate for that without MCAS.

  11. ChrisBCN,
    Every Airbus is “fly by wire”. There is no physical connection between the pilot’s controls and the rudder, ailerons and elevator. It is 100% software controlled. Theoretically, an Airbus is supposed to be programmed so that pilot inputs that put the aircraft outside its flight envelope are ignored.

    Yet, they still manage to crash.

    Boeing is not innocent by any means but thousands and thousands of segments were flown in this aircraft safely prior to the two crashes. I believe that properly train crews would have safely landed both those aircraft.

  12. @ChrisBCN

    Generally Airbus aircraft are the most automated and many systems cannot be totally turned off. Until the Max, most Boeing aircraft could be flown totally by manual control. But most airlines require that the “auto-pilot” be engaged shortly after takeoff and disengaged in the last 1,000-1,500 feet before landing. Automation prevents simple errors and that is why airlines require it. There are aircraft that can take off, fly and land without any pilot input. We should get used to total automated flying as this will be the only way in the future.

  13. I have written on this before:
    –Starting with the 787, Boeing has outsourced both engineering and manufacture of airplanes. The 787 had a lot of problems (ie. plane parts not fitting together, burning planes, guesses on how composite materials would hold up to flight…..), but Boeing was lucky none turned out to be fatal.
    –Boeing’s management cut a lot of corners in designing the 737 Max as they outsourced (a) the manufacture of parts to other countries, (b) general engineering to India, and (c) parts engineering to parts manufacturers.
    –Senior management that drove Boeing’s engineering culture into the so called “ditch” are still running the Boeing.
    –Management at Boeing has not been fired. It does not appear to me that they have done a wholesale re-examination of operations (like BP did after the Gulf Oil Spill) required to fix the internal Boeing culture of shortcuts and outsourcing.
    –All I have heard from management is sanctimonious statements about how much their employees care about safety while they were trying to cover-up problems with the 737 Max 8.
    –WTH, the USA assemblers of 737 Max 8 cannot control the safety of the internationally outsourced designed plane and the quality of parts being shipped from around the world just by caring a lot.
    –After worldwide scrutiny, I am guessing that the 737 Max 8 will be safe enough. I will fly.
    –I will avoid the new 777x planes for several years after they are introduced. I do not want to be on a plane when it doors fly off, or the wing breaks off, or something like that.

  14. ** and you will probably will too.**

    Come on, man. Cut one of those wills and try proofing this stuff on occasion.

  15. The David Dao analogy is 100% misplaced. It is easy to avoid becoming David Dao – just get off the plane when you are told. It is not easy to avoid a 737 MAX crash because that’s entirely in the hands of Boeing and the pilots.

    It will be easy for travelers to avoid the 737 MAX by picking other flights. I certainly will. If enough people do so there will be lots of discounts available for you brave few (just as there were after 9/11). After a year maybe I will trust them but certainly not after a month, no matter how many airline and Boeing families take test flights.

  16. 1 and 2 are not controversial. 3 is wrong. MAX is the proof.

    Gary no doubt has reviwed a sample of expert opinions. But without being an expert, how can anyone really tell which opinions are correct.

    Gary us offering an opinion on MAX safety the same as everyone else.

  17. The MAX is an aerodynamically flawed airplane and you cannot fix an aerodynamic flaw with a piece of software.

    Gary probably got a goodie bag and a boeing hat for free from Boeing to write this article.

  18. #1 is totally inaccurate. The pilots the day before were NOT able to overcome MCAS. As matter of fact the jet would have crashed that day if there was not an off duty pilot in the cockpit. The 2 pilots were fighting to save the plane like in the other crashes. The only reason the jet did not crash that day because the off duty pilot not flying was able to analyze the situation and come up with a solution. If the off duty pilot was not there the plane would have crashed. If he had actually been the pilot it would have probably of crashed because he would have been focused on fighting with the MCAS system to keep the jet in the air.

  19. What most people forget to mention is that Boeing built the MAX in retaliation to Airbus having the Neo and American airlines saying that it will look forward to a new engine configuration from Boeing. In this case, it’s the blame of laziness and aggressive assertion by a customer to make it. Boeing was lazy in not designing a new plane from the ground up, rather relying on a dated model that was perfect for the 1960s. The placement of the engine caused the air flow under the wings to be greater in relation to the flow above that would make it airborne, i.e. much greater than required. Then there is the case on American airlines, they literally pressured Boeing into designing a new engine model of the 737 in an internal memo after air bus released the Neo, where is the blame on American for this? People keep forgetting, it’s the laziness of the American stigma and competition that made the lives of 264 lost.

  20. In short, just look back into time to the late 1950s/early 1960s when the Lockheed Electra posed similar issues-the engines were too powerful/faster than the wings could tolerate. The arrival of the B707 and DC8 resolved that issue.

  21. Airbus have three AoA systems, and use all three. Boeing had two, and used one.

    As a pilot with almost 20,000 hours flying various Boeings, I won’t be getting on a MAX if it is in any way avoidable. Until we see triple AoA probes they will have done nothing more than patch it…not fix it.

  22. All jet transports built today require software to behave as certified. The MAX’s distinction is that it needs a kludge to be relatively stable. In his comment, Gary got it backwards. The first 737s had the option of carrying stairs, and had straight-pipe engines. Transport engines are getting more efficient by having higher bypass ratios: you have a jet in the middle that spins a big fan that blows most of the air around the engine. So fans get bigger and faster, to the point that, starting with some DC-10s, the fan blades go supersonic on takeoff (that hammering noise). The latest engines are more efficient still (and quieter), this even bigger.
    But the 737 is still built for stairs, and redesigning the landing gear would involve significant regulatory and engineering hurdles. So they moved the MAX’s engines forward, in front of the wing.
    That’s fine, but when the plane pitches up, at dinner point them giant engine pods produce lift, pitching the plane further up. This is like a car with severe oversteer that kicks in all at once, only pitching up.
    So they put MCAS in there to make the stick feel normal in that situation. And they screwed up. And yes, every accident has a chain of causes, but this approach to design betrays a concern for meeting every formal requirement at the expense of actual safety.

  23. @Ronny _ I have had absolutely zero contact with Boeing other than a factory tour open to all other participants on the oneworld megado event in january 2012.

  24. The design of the 737 is inherently flawed. And Boeing was irresponsible (greedy) in bringing that poor airframe to market. Never mind the FAA’s culpability and egregious lack of oversight.

  25. In the meantime, stock trading is halted this morning (as of 9:05AM 12/23/19), pending a big announcement at Boeing. Even though it is morning, I think I will get out the popcorn.

  26. David Dao is not a pile of fragments no larger than a millimeter across. That comparison is so ridiculous it shows that you lack a firm grasp of reality and invalidates the article.

  27. @Boraxo —>. “It will be easy for travelers to avoid the 737 MAX by picking other flights.”

    In the SHORT term, sure…if you’re willing to either take a different airline (look at how many MAX planes both American and Southwest has currently grounded and on order), or (possibly) forego a nonstop and take a hop “here” and change planes…you could stay on regional jets and/or “puddle-jumpers.”. Long-term, it will be much more difficult.

    Like most here, I’ll be (trying to) avoid the MAX in the short term when it eventually returns to service, but inevitably I have no doubt I’ll be on several over the course of my life…


    @Keith —>. “The design of the 737 is inherently flawed.”

    An analysis by Boeing on commercial jet airplane accidents in the period 1959–2017 showed that the Next Generation series had a hull loss rate of 0.17 per million departures versus 0.71 for the classic series and 1.75 for the original series. (Doesn’t sound flawed to me.)

    The 737 was the most widely sold airliner until October 2019, when Airbus took the lead following the MAX crashes, but remains the most commonly flown aircraft. As of November 2019, 15,156 units of the Boeing 737 have been ordered — 10,565 have been delivered, and 4,591 units either waiting to be built, or waiting to be delivered.

  28. Boeing just fired the CEO. The Executives are being pushed away, out of the process chain. After months of pretending they could cruise to an easy fix and quickly resume shipments of the plane, the company is now treating this as an existential emergency, as they should. The full resources of the company are being unleashed to make damn sure the fix is complete and correct. If they got this plane re-certified, and there shortly was another incident, it would be a decade or more before they would regain their reputation – not to mention how far the stock would crash.
    Hell yes, I’ll fly on the re-certified plane when it comes to it.

  29. I for one would prefer it to be grounded permanently. Boeing chose short term profits versus long term gain when they chose to retrofit a 40+year old design versus create a modern aircraft. The plane is flawed as it was never designed to operate this way. This company created the incredible 707 and 747 along with other great aircraft. It boggles my mind why they chose to skip doing that again and just stick with the same OLD design. Oh yeah, short term profits. Sad really.

  30. I would fly this aircraft with no hesitation. Boeing has a couple of issues. The 737 Max is a first world aircraft being sold to and flown by third world airlines with third world maintenance and third world under trained pilots.
    The second major issue at Boeing is that it always was an engineering company until it hired GE trained marketing senior staff. Welch F’d up GE when he decided to sell money instead of building products. These same people now think it is better to have 6000 subcontractors instead of building the aircraft from design to runway. Who now runs Boeing? Another GE Welch trained spinoff. I fear for the future of this great company.

  31. Thanks, Gary, for being the voice of reason, and the adult in the room, on a topic that’s been over-sensationalized by unqualified clickbaiters.

  32. I will fly the Boeing 737Max when they are put back into service. I won’t fly with dodgy foreign airlines, especially Asian airlines, though. Their pilots make too many errors and have inadequate training and experience.

  33. As a retired pilot and software engineer, it seems obvious to me that the 737 Max can never be an inherently safe plane. The fundamental problem is that you have an aircraft frame that was designed for turbojets being modified to accept much larger turbofans. Using software to overcome this fundamental design deficiency is sheer madness. They should have come out with a completely new design.

  34. I think software-augmented controls will become much more common. For example, flying at an aerodynamically neutral point will result in maximum fuel efficiency, but it’s very hard to do, as a pilot flying manually. Computer-controlled balance could compensate for that, and perhaps the fuel savings would be compelling. With adequate pilot skill and training, such software-controlled flight would be safe and profitable. Watch for it…
    As for the MAX, I’d happily sign up for the first MAX SWA flight going where I need to go. Not sure I’d fly on any 3rd- or 4th- world airline flying anything.

  35. I agree with Gary that the MAX will eventually fly again, but honestly it probably shouldn’t in its current configuration. I vehemently disagree with @Gary’s assertion that: “..The moved engines give the aircraft a tendency to pitch down under certain conditions. A pilot can compensate for that without MCAS.” This requires the pilots to turn off MCAS and use the manual trim wheel. It has been shown in the sim that smaller pilots may not have the physical strength to move the manual trim wheel. That’s a problem when you’re trying to fly the aircraft. Can one fly an aircraft with screwed up trim? Maybe. But it’s never pretty. There’s a reason there’s a cockpit circuit breaker on all electric trim in case it runs away from you.
    The problem as I see it, is that the B737 is a true geriatric jet. The 737 entered service in 1968. Yes, I know the B52s are still flying from the ’50s and that the F16 could not fly without software, but we are talking a passenger jet here, not a warplane. Boeing tried to slap lipstick on a pig by re-engineering the 737 to accept physically larger engines that just don’t fit, need to be relocated forward and up, which completely changes the moment of the aircraft. Enter the failed MCAS system to fix that problem. Understand: MCAS uses trim to attempt to stabilize what Boeing produced. An inherently unbalanced aircraft. Comforting isn’t it? This was made clear to me at CEB in the last week when I saw an older B737 probably a -200 at CEB with the original engines. Go look at an older B737 v a B737-MAX and you will see the difference in engine location.
    It is also clear Boeing concealed or obfuscated the flaws with MAX from regulatory bodies.
    Endgame: Will I fly the MAX when (if) it re-enters service? Of course. I won’t have much of a choice.
    BUT: Airlines have managed without the MAX for 6+ months. Were I them I would give them back to Boeing as a flawed platform and suck up used Airbus 320 and 321s in the secondary market until I could get new aircraft from Airbus (not a geriatric jet). Delta does very well using older used aircraft, so others should be able to too.

  36. Boeing issues go deeper than the Max! When you move the headquarters away from engineers and manufacturing and hire non engineers as CEOs you’re asking for trouble. The 777 was the last aircraft from Boeing without the major hiccups Such as that that have plagued the later 737 models and Dreamliner.

    Yes. I will probably fly the Max again but not without a little anxiety over the patchwork and lack of experienced leadership!

  37. @Patrick —>Agreed, and something I’d forgotten about, but I remember thinking when they moved out of Seattle that is was a stupid idea….

  38. The 737 WAS a good aircraft (first flew in 1969) but when airlines wanted Boeing and others to design planes that could cram ever more of us into even less space and be able to do long hauls, using less fuel, Airbus was designing new from scratch, Boeing just updated the avionics and slapped some new more fuel efficient and LARGER engines on the jet. Double the compression from 11 to 22, and some other changes that most people would not understand or care about. The problem was that even with the flattened bottom of the engine cowl there was insufficient ground clearance so Boeing had to move the engines forward and up attached to the wings with nacelles.

    The tops of the engine cowling now rises above the leading edge of the wing and the new position is inherently unstable. That was why the had to install the MCAS system in the first place. Had they installed two ACA sensors the plane would have to have been recertified, a long and expensive process so they only used one and that was already known to be faulty and prone to icing. That was why they could not fly it into cities where icing conditions were likely in bad weather. On top of that the pilots would have to have undergone additional simulator training and recertification rather than just an information video on their iPads.

    These were all decisions made by a company which is putting it’s profits ahead of passenger safety and that was inevitable as the TSA and FAA and other regulators have spent years pissing on passengers as to comfort and safety. Yeah let’s give passengers 16 inch wide seats and 4 inches of legroom. I had to fly from LA to Auckland in the middle of the back row against the bulkhead (with a whopper of a cold) and was nearly ready for an ER by the time we landed more than 14 hours later, my feet never touching the ground because my knees had to be up against the seat in front of me about where that passenger’s should blades were. You think business and governments that treat you like this have any more concern for safety over profit?

    Whatever you say Mr. Leff, you know your stuff and I respect your opinion, but you do not know me or millions of other people that are pissed off and scared of this jet. I do not care how well they fix it, until justice is done and some Boeing decision makers go to prison for 346 counts of manslaughter I will not ever get aboard those planes. It will mean paying a lot more for refundable tickets so that when I go to board if there is a Max at the gate I can get my money back as I head to another airline.

  39. If you know you are on a 737 but don’t know what type, I’m assuming that if you look out the window of the boarding gate and see scalloped edges on the rear of the engine cowling, it would be a 737 MAX.

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